Supported HTML Subset doesn't work correct if a table is in a table

Hallo,

in Qt Documentation are several supported HTML subset, but they work only in a simple table.
it doesn't work always correct if a table is in a table.

you can quickly check it by opening the attached file in a webbrowser (for example firefox) and then opening the same file in the official textedit demo ( qt/demos/textedit/ ). of course the sample file is a valide html source (i check with html validator)

you can see the coloring a table in a table work fine.
but changing the border style of a td of table in a table fail. it work only in the "main" table, but not in the "subtable".

please check attached file.
styleing tables is highly needed to get nice timetables (of yourse i don't style them like in the attached file. i just styled them that way to have a good sample file to fix that bug.)

i hope someone is able to fix it,
regard
V. Dirr